Substantial effort has heretofore been expended in development of rotary valve apparatus for internal combustion engines. This effort is warranted because of the basic inefficiency of the conventional type of reciprocating valves that have been almost exclusively utilized for such engines. The reciprocating type of valve substantially interferes with gas flow in that the valve head is always disposed in the path of the gases resulting in flow-path distortion that materially reduces and restricts the gas flow into or out of a cylinder. Furthermore, mechanical actuation of reciprocating valves represents an additional energy loss in view of the numerous components that are necessary for operation. While a cam in head engine eliminates the push rods that are otherwise required, the cam mechanism does include levers and springs for maintaining the valves in a closed position. The levers and springs require expenditure of a certain amount of energy for operation which further reduces engine efficiency.
Rotary valve mechanisms known to have been developed for internal combustion engines has either comprised elongated tubes that connect with several cylinders or disc-type valve elements disposed in each cylinder. Neither of these two types of rotary valve mechanisms have been found to be as effective or as efficient as desired or possessing sufficient advantages over the reciprocating valves.